Abstract:
The need to find natural replacements for synthetic hormonal anabolic steroids for use in
livestock production has received considerable attention in the recent past. The present study
was, therefore, designed to assess the efficacy of using testicular tissue or fluid on the
development of Tilapia fish species (Oreochromis andersonii). In the first of two experiments, a
48% crude protein fry diet was formulated to contain 50% testicular tissue powder and 50%
commercial fry diet. Fry were fed either twice (n=50), thrice (n=50) or four (n=50) times daily
for 28 days. For an additional 32 days, fry were fed commercial fry feed. Mean weight, Standard
length and total length of fry were not affected by feeding fry with testicular tissue. Similarly,
increasing the frequency of feeding did not influence fry weight, standard or total length. In the
second experiment, fry were fed a diet that contained steroid-free testicular fluid or feed that
contained neat testicular fluid. The 45% crude protein ration was given to O. andersonii twice
daily for 28 days. Fry were fed a commercial fry ration for an additional 32 days. Testicular fluid
inclusion significantly affected final weight (0.12 0.005g vs 0.099 0.004g, P=0.002), total
length (1.91 0.03cm vs 1.81 0.03cm, P=0.02), and standard length (1.50 0.03cm vs
1.39 0.02cm, P=0.003). It is concluded that use of testicular fluid extract is a convenient tool
that enhances fish fry performance and may have potential for stimulating improved fry and fish
growth to improve aquaculture productivity especially among smallholder farmers. |
